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Old 31-07-2018, 02:09 PM
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sil (Steve)
Not even a speck of dust

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Join Date: Jun 2012
Location: Canberra
Posts: 1,474
It'll be a common generic consumer telescope. It'll be nicely built and branded it it was a quality product and would have cost much much more new and second hand. Doesn't mean its crap, the problem with the low end telescopes is not the tube usually (especially with reflectors) the problem is with the eyepieces. its certainly usable but not a wise purchase to begin with. My first astrophotos of planet was with something cheaper and nastier, but with good Baader eyepieces it gave crisp spectacular views.

The biggest problem with scope (any many will disagree) is "optics", meaning the mirrors and lenses that bend and focus the light. each optical part degrades the quality of the light that ends up in your eyes, most of which are inside the eyepiece. people assume its the big tube at fault instead. On a reflector its mostly just mirrors the photons touch and making reflective surfaces is fairly easy at consumer grade sizes so there is typically good transmission of light with those. However the clear/magnifying elements (the "lenses" ) have to allow photons in the front and out the back but all transparent substances refract light (ie want to split white light into rainbows), glass is better than plastic which cheap optics systems often contain. plus different chemical formulations of the glass perform differently. More elements in the train are often used to try to recombine the photons from rainbow to white again as light travels through them. Same as in camera lenses. So usually the front element refracts the light a lot and the light at the edge gets bent more and starts to split quicker than in the middle. the next element tries to correct that and get the photons travelling parallel again to the next focusing element with another corrector etc. the goal is for photons to be travelling parallel (at the same speed) when they exit the end of the optical train just as they were entering the front so the image is crisp and undistorted wshen it reaches your eye or a camera sensor.

A cheap reflector is mostly mirrors (easy cheap to make) and very few lenses (very difficult and costly to make) then the eyepiece is all lenses. A cheap refractor scope is all lenses plus the eyepiece so theres nothing much possible to improve those.

so the let down with a bargain reflector is likely to be with the eyepieces, a quality eyepiece will vastly improve the views and I think a camera should work fine too (but it'll be very high magnification as it acts like a 6mm eyepiece and atmospheric distortions come into play in a big way when you go below 10mm.

If you're serious buy a Baader eyepiece (very good value for money, they dont make any crap budget eyepieces at all. Pick up a 10mm followed by something around 25-30mm and thats all you need mostly. Eyepieces come in 1.25" and 2" standard sizes, so your current scope probably uses 1.25" as do most scopes under $1000 I think, so the eyepieces will work in any future scope you buy pretty much. Or you can waste money on cheap eyepiece sets assuming lots of eyepieces is good value and you'll spend heaps and a ton of time coming to the conclusion if you'd ignored the shiny new toy impulse and bought something of good quality straight away you'd have been up and running with great viewing years earlier. You'll notice most people have Televue eyepieces because they know the truth of good eyepieces and TVs are high end quality at a good price. There are better technically which can cost many times more (there is no limit to spendng in astronomy) but its the plateau everyone typically reaches, just up to you how many times you want to "upgrade" on your way to the same finish and what that'll cost. Baader had a great midrange set when I started and grabbing a few of those and their Zoom eyepiece elevated my astronomy greatly and with my failing eyes I didnt progress to the Televues. Baaders are down in price these days and have better quality range, morpheus i think its called, And I think this would be a wise buy right now. a 10mm first to give you crisp high magnification under most "seeing conditions", and something around 25mm to 30mm for a wider view of large items and just to help you star hop and navigate with visual (very hard to do with 10mm) and i think those two cover the biggest needs of everyone for their lifetimes so buying smart on these will suit you forever. any scope you buy will have kit lenses I bet are worse than the Baaders. Ideally a baader zoom but it can have problems getting to focus on some cheap scopes with poor quality focusers, but their regular eyepieces should be fine. Optically the zoom is not noticably worse quality to my eyes and its easier than swapping around eyepieces. With a zoom you can keep note of the ranges you use all the time and then use those to guide your purchase of the right size Televues for your needs.
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